Fuel basket spacer, apparatus and method using the same for storing high level radioactive waste

An apparatus for containing radioactive materials having a residual heat load comprising:

• a body comprising an inner surface that forms a cavity for receiving radioactive materials, the cavity having an open top end and a closed bottom end;
• a basket positioned in the cavity and comprising a plurality of cells, the basket having a horizontal cross-sectional profile having an external perimeter formed by an outer surface of the basket;
• a plurality of ring structures having a top surface, a bottom surface, an outer surface, and an inner surface forming a central passageway, the ring structures arranged in a stacked assembly within the cavity so that the top and bottom surfaces of adjacent ring structures in the stacked assembly are in direct surface contact with one another, each of the ring structures having a horizontal cross-sectional profile having an internal perimeter formed by the inner surface of the ring structure and an external perimeter formed by the outer surface of the ring structure;
• and
• wherein the basket extends through the central passageways of the ring structures so that an entirety of the external perimeter of the basket is in conformal surface contact with the internal perimeters of the ring structures.

An apparatus for containing radioactive materials having a residual heat load comprising:

• a body comprising an inner surface that forms a cavity for receiving radioactive materials, the cavity having an open top end and a closed bottom end;
• a basket comprising a plurality of cells positioned in the cavity, the basket having an outer surface;
• a plurality of ring structures having a top surface, a bottom surface, an outer surface, and an inner surface forming a central passageway, the ring structures arranged in a stacked assembly within the cavity;
• and
• the basket extending through the central passageways of the ring structures so that an entirety of the outer surface of the basket is in conformal surface contact with the inner surface of the ring structures.

An apparatus for containing radioactive materials having a residual heat load comprising:

• a body comprising an inner surface that forms a cavity for receiving radioactive materials, the cavity having an open top end and a closed bottom end;
• a basket comprising a plurality of cells positioned in the cavity, the basket having an outer surface;
• a plurality of ring structures having a top surface, a bottom surface, an outer surface, and an inner surface forming a central passageway, the ring structures arranged in a stacked assembly within the cavity;
• and
• the basket extending, through the central passageways of the ring structures so that a first clearance exists between the inner surfaces of the ring structures in the stacked assembly and the outer surface of the basket at ambient temperature, the first clearance circumferentially surrounding the basket;
• and
• wherein upon radioactive materials having, a residual heat load being positioned in the basket, the residual heat load from the radioactive materials causes the basket to expand so that an entirety of the outer surface of the basket is in conformal surface contact with the inner surfaces of the ring structures and the first clearance is eliminated.